Decreasing Knee Injury Risk Factors With Neuromuscular Training

Brief Title

Decreasing Knee Injury Risk Factors With Neuromuscular Training

Official Title

The Effectiveness of Neuromuscular Training on Modifiable Anterior Cruciate Ligament Injury Risk Factors

Brief Summary

      Anterior cruciate ligament (ACL) tears are disabling injuries that place a significant burden
      on the athlete. Roughly 80% of these injuries are linked to a noncontact mechanism, with more
      than 70% of them occurring while landing from a jump. Female athletes are at higher risk of
      sustaining a noncontact ACL injury due to the higher number of risk factors that they possess
      compared to their male counterparts. Due to this statistic, ACL prevention programs have been
      developed over the past 15 years in attempt to reduce this risk among the female athletic
      population. These programs have been shown to reduce the rate of noncontact ACL injuries in
      females by correcting the risk factors associated with them. However, it remains unclear as
      to whether these positive results are solely due to the program or a higher exercise workload
      in its participants. The purpose of this study is to evaluate the effectiveness that an ACL
      prevention program has on modifying at-risk landing mechanics (associated with noncontact ACL
      injury) compared to a resistance training program of equal workload.
    

Detailed Description

      Injury Background Anterior cruciate ligament (ACL) tears are disabling injuries that place a
      significant burden on the athlete. The average cost for ACL reconstruction is estimated to be
      approximately $17,000 per patient and full recovery commonly takes around 6 months to
      achieve. It has been estimated that 1 in every 3000 people in the United States suffer an ACL
      rupture each year. Roughly 80% of these injuries are linked to a noncontact mechanism, with
      more than 70% of them occurring while landing from a jump.

      Injury Mechanism Upon landing, the lower body falls into what is referred to as the
      "position-of-no-return" (PNR). The landing kinematics involved with the PNR places a high
      amount of stress on the ACL and can ultimately lead to a complete rupture.

      Injury Imbalance Female athletes who participate in sports that involve jumping and cutting
      activities suffer 4-to-6 times more ACL injuries than males who participate in the same
      sports. This is attributed to the higher number of risk factors that females possess during
      and after puberty. In particular, upon maturation, males exhibit a neuromuscular spurt, with
      increases in power, strength, and coordination, whereas females do not. Other risk factors
      that females demonstrate are quadriceps dominance and ligament dominance. Both of these
      dominances are linked to the landing kinematics of the knee when placed in the PNR.

      Quadriceps dominance is characterized by the extended knee posture that is displayed in the
      PNR when landing from a jump. When landing on an extended knee, the tibia is translated
      anteriorly to the femur, causing the ACL to become taunt. In order to prevent the ACL from
      rupturing, the hamstrings must activate to flex the knee and translate the tibia posteriorly.
      In response to anterior tibial translation, females are found to utilize a different muscle
      recruitment pattern than males by contracting their quadriceps before their hamstrings,
      whereas males follow the opposite pattern. By contracting the quadriceps first, the
      hamstrings are overpowered, which allows for further anterior tibial translation to occur
      during landing.

      Ligament dominance is evidenced by the increased knee valgus that displayed in the PNR when
      landing and cutting. During these maneuvers, females rely on their knee ligaments rather than
      lower extremity musculature to absorb ground reaction forces. This tendency places a high
      amount of stress on the ACL, which in turn, increases the probability of it rupturing.

      Injury Prevention Due to the high rate of noncontact ACL injuries seen in female athletes,
      neuromuscular training (NMT) programs have been developed in an attempt to prevent or reduce
      the risk of injury. These programs are administered as either an off-season regimen or
      in-season warm-up routine, and they incorporate a combination of plyometric, proprioceptive,
      and strength training exercises, with particular focus being placed on correct technique. By
      modifying neuromuscular risk factors, NMT programs have been able to significantly reduce the
      rate of noncontact ACL injury.

      Specific Aim 1:

      To evaluate the effectiveness that an ACL prevention program has on modifying at-risk landing
      mechanics (associated with noncontact ACL injury) compared to a resistance training program
      of equal workload.

      Specific Aim 2:

      To evaluate the effectiveness that an ACL prevention program has on improving max vertical
      jump height compared to a resistance training program of equal workload.
    

Study Type

Interventional

Primary Outcome

Change in Knee separation during the Drop Jump Test

Secondary Outcome

 Changes in Vertical Jump Test

Condition

ACL

Intervention

Neuromuscular and Resistance Training

Study Arms / Comparison Groups

 ACL prevention training

Description:  

Publications

* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.

Recruitment Status

Procedure

Estimated Enrollment

0

Start Date

September 2011

Completion Date

June 2012

Primary Completion Date

February 2012

Eligibility Criteria

        Inclusion Criteria:

          -  Female college underclassman (ages 18-20)

          -  Body Mass Index (BM) between 18.5 - 25 (normal range)

          -  Blood pressure below 140/90 (below hypertension)

          -  History of participation in high school athletics

          -  Signed Informed Consent form

        Exclusion Criteria:

          -  History of ACL injury

          -  Current/ongoing knee condition

          -  History of surgical intervention within one year (not including facial)

          -  Current/ongoing musculoskeletal injury

          -  History of previous ACL prevention training

          -  Currently involved in intercollegiate athletics

          -  Currently Pregnant
      

Gender

Female

Ages

18 Years - 20 Years

Accepts Healthy Volunteers

Accepts Healthy Volunteers

Contacts

Conrad M Gabler, B.S., , 

Location Countries

United States

Location Countries

United States

NCT ID

NCT01433718

Organization ID

Ohio_U11F024

Secondary IDs

1104MGP005

Responsible Party

Sponsor

Study Sponsor

Ohio University

Collaborators

 National Athletic Trainers' Association Research & Education Foundation (NATA Foundation)

Study Sponsor

Conrad M Gabler, B.S., Principal Investigator, Graduate Athletic Training Student

Verification Date

April 2017